Outerwears was created to fulfill a desperate need to keep the Air filter and engine clean during off road racing. Racers and engine builders were experiencing loss of horsepower and engine damage due to sand, dirt, and other debris prematurely packing (clogging) the filter and often passing through the filter into the engine. Filters loading up with dirt meant loss of horsepower and in many cases loss of a race. Race crews were noticing severe engine damage due to dirt entering into the engine. Thus, a true need for a product designed to keep out additional dirt without interfering with airflow was necessary. Skip ahead to today, and the widely used Pre-filter can be seen on a variety of applications from circle track racing, street, motocross, jet-ski, ATV, snowmobile, kart, military, industrial machinery, and consumer appliances. Outerwears has a product for virtually any air intake application. Pre-Filters unique polyester material contains uniform, micron-sized openings to allow air in while filtering out the grime that will eventually clog an air filter or breather.Pit Stop USA offers Outerwears 3" Non-Shielded Crank Breather Pre-Filter w/o Top - Black 10-1013-01 at low everyday prices. Be sure to check out all of our products from Outerwears Performance Products including Outerwears Performance Products Air Filter and Breather Pre-Filters and Outerwears Performance Products Valve Cover Breather Pre-Filters and Outerwears Performance Products Breather Pre-Filters.